Pulsing headlight only when on high beams
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It may be just a bad bulb. It could also be a bad ground. Dakota's can sometimes be known for bad ground problems. There is a ground lug located on the right side fender well, under the air intake snorkel area. I would bet money that the right side headlight bulb is grounded there. Maybe loosen the ground nut and use a wire brush to clean the connector, nut and the ground lug itself down to bare shiny metal. Go ahead and replace the ring terminal ground connector if the wires on it look corroded. There is another ground lug on the left fender well, one in the left wheel well grounded to the frame behind the left front tire and one in front of each valve cover on the engine block. There are ground lugs in the metal areas of each kick panel too, this would be a good time to give all of your grounds the same clean-up treatment.
The CTM does have a dedicated left and right high beam output, so that could be the problem too. The only way to diagnose the CTM for sure is at the Dodge dealer, they have to use the DRB-III scan tool to check the CTM's operation. You can replace the CTM yourself if it is bad, it is located in the driver's kick panel. If you have the factory installed keyless entry system, the dealer will have to program your original keyless entry remotes to the new CTM, because the keyless module is an internal part of the CTM. I would say check the grounds and bulb first, also check all the associated wiring to the headlight too before checking or replacing the CTM.
An edit here: If the bulb, wiring and grounds are all OK, maybe check the output at the bulb from the CTM. At the right headlight the high beam wire should be red with an orange stripe. When that high beam light starts blinking and acting up, maybe check the orange/red wire with a volt meter. If you get pulsing or fluctuating voltage on it that is in sync with the blinking of the headlight, you probably do have a bad CTM.
Jimmy
The CTM does have a dedicated left and right high beam output, so that could be the problem too. The only way to diagnose the CTM for sure is at the Dodge dealer, they have to use the DRB-III scan tool to check the CTM's operation. You can replace the CTM yourself if it is bad, it is located in the driver's kick panel. If you have the factory installed keyless entry system, the dealer will have to program your original keyless entry remotes to the new CTM, because the keyless module is an internal part of the CTM. I would say check the grounds and bulb first, also check all the associated wiring to the headlight too before checking or replacing the CTM.
An edit here: If the bulb, wiring and grounds are all OK, maybe check the output at the bulb from the CTM. At the right headlight the high beam wire should be red with an orange stripe. When that high beam light starts blinking and acting up, maybe check the orange/red wire with a volt meter. If you get pulsing or fluctuating voltage on it that is in sync with the blinking of the headlight, you probably do have a bad CTM.
Jimmy
